Monster Hunter: World - 10 Hardest Monsters (And How To Beat Them)
2. Nergigante
The Elder Dragon that feeds on other Elder Dragons: that should tell you all you need to know about this hellspawn.
I loathe to say it, given that the comparison has, at this point, become a cliche, but your one-on-one with Nergi should be tackled with a Dark Souls mindset. That is, success won't be earned through luck, but trial and error. There are no gimmicks here, just a straight fight between hero and a walking fortress of bone and pure hatred.
The best advice I can offer is to invest - if you haven't already - in a crushing weapon. This'll work a treat in breaking through Nergigante's solid shell, just be wary of his ability to lurch at you sideways with hefty force.
Adequately geared, all but one of his attacks (the dive bomb) is survivable, but the insta-kill attack is clearly telegraphed ahead of time. A Flash Pod between the eyes will lead it to fluff the manoeuvre, though once you've run dry of those, dodging into the dive will ensure that it goes clear overhead.
You will die during this test of endurance, but as long as each fresh attempt is met with progress, you'll be well on the way to victory. God speed, Hunter.